I can't seem to start a GDB session correctly

[TBPLtd]

Windows 10!
I'm using gdb as the debugger. I've checked the version is 14.1 and can use it with the target executable in a terminal, sucessfully setting breakpoints etc. When I do so and check the running processes, gdb has a file handle to the target executable.
When I start a session within neovim (using dapui) I can see gdb starts as a subprocess of nvim-qt, but it never gets a file handle to the target executable. I've tried adding ${file} to the launch args and some other permutations from t'internet all give the same results.
I have added a 'clean' log file set for TRACE below. All looks good, all requests are answered success = true. Breakpoints are set etc.
However, one oddity, the REPL panel replicates a message from the log 'No source file named xxx.cpp.' This file does exist. The REPL panel immediately follows this with 'Breakpoint 1 (-source xxx.cpp)' the same file which I find odd.
I think I'm just not starting ( dap.continue()) properly.
Configuration lua and dap.log follow and help very much appreciated.

return {
  "mfussenegger/nvim-dap",
  dependencies = {
    "rcarriga/nvim-dap-ui",
    "nvim-neotest/nvim-nio",
  },
  config = function()
    require("dapui").setup()
    local dap = require("dap")
    local dapui = require("dapui")
    -- local nio = require("nio")
    dap.listeners.before.attach.dapui_config = function()
      dapui.open()
    end
    dap.listeners.before.launch.dapui_config = function()
      dapui.open()
    end
    dap.listeners.before.event_terminated.dapui_config = function()
      dapui.close()
    end
    dap.listeners.before.event_exited.dapui_config = function()
      dapui.close()
    end --
    dap.adapters.gdb = {
      type = "executable",
      command = "gdb",
      -- args = { "-i", "dap" },
      args = { "--interpreter=dap", "--quiet" },
      -- # Could try --quiet --interpreter=dap
    }
    dap.configurations.cpp = {
      {
        type = "gdb",
        request = "launch",
        name = "C/C++ Debugger",
        program = function()
          return vim.fn.input({
            prompt = "Path to executable: ",
            default = vim.fn.getcwd() .. "/",
            completion = "file",
          })
        end,
        args = { "${file}" },
        cwd = "${workspaceFolder}",
        stopAtBeginningOfMainSubprogram = false,
      },
    }

    local map = function(keys, func, desc)
      vim.keymap.set("n", keys, func, { desc = "Dbg: " .. desc })
    end
    map("<Leader>db", dap.toggle_breakpoint, "Toggle Breakpoint")
    map("<Leader>dB", dap.set_breakpoint, "Set Breakpoint")
    map("<Leader>dc", dap.continue, "Continue")
    map("<Leader>di", dap.step_into, "Step into")
    map("<Leader>do", dap.step_over, "Step over")
    map("<Leader>de", dap.terminate, "Terminate session")
    map("<Leader>due", dapui.toggle, "Exit DAPUI session")
  end,
}

dap.log

[ DEBUG ] 2024-06-10T21:09:48Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:1387 ]	"Spawning debug adapter"	{
  args = { "--interpreter=dap", "--quiet" },
  command = "gdb",
  type = "executable"
}
[ DEBUG ] 2024-06-10T21:09:48Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:1711 ]	"request"	{
  arguments = {
    adapterID = "nvim-dap",
    clientID = "neovim",
    clientName = "neovim",
    columnsStartAt1 = true,
    linesStartAt1 = true,
    locale = "en_US",
    pathFormat = "path",
    supportsProgressReporting = true,
    supportsRunInTerminalRequest = true,
    supportsStartDebuggingRequest = true,
    supportsVariableType = true
  },
  command = "initialize",
  seq = 1,
  type = "request"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  body = {
    exceptionBreakpointFilters = { {
        filter = "assert",
        label = "Ada assertions",
        supportsCondition = true
      }, {
        filter = "exception",
        label = "Ada exceptions",
        supportsCondition = true
      }, {
        filter = "throw",
        label = "C++ exceptions, when thrown",
        supportsCondition = true
      }, {
        filter = "rethrow",
        label = "C++ exceptions, when re-thrown",
        supportsCondition = true
      }, {
        filter = "catch",
        label = "C++ exceptions, when caught",
        supportsCondition = true
      } },
    supportTerminateDebuggee = true,
    supportsBreakpointLocationsRequest = true,
    supportsConditionalBreakpoints = true,
    supportsConfigurationDoneRequest = true,
    supportsDelayedStackTraceLoading = true,
    supportsDisassembleRequest = true,
    supportsEvaluateForHovers = true,
    supportsExceptionFilterOptions = true,
    supportsFunctionBreakpoints = true,
    supportsHitConditionalBreakpoints = true,
    supportsInstructionBreakpoints = true,
    supportsLoadedSourcesRequest = true,
    supportsLogPoints = true,
    supportsModulesRequest = true,
    supportsReadMemoryRequest = true,
    supportsSetExpression = true,
    supportsSetVariable = true,
    supportsSingleThreadExecutionRequests = true,
    supportsSteppingGranularity = true,
    supportsTerminateRequest = true,
    supportsValueFormattingOptions = true,
    supportsWriteMemoryRequest = true
  },
  command = "initialize",
  request_seq = 1,
  seq = 1,
  success = true,
  type = "response"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  event = "initialized",
  seq = 2,
  type = "event"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:1711 ]	"request"	{
  arguments = {
    cwd = "D:\\Users\\Graham\\Projects\\C++\\Sandbox",
    name = "C/C++ Debugger",
    program = "D:\\Users\\Graham\\Projects\\C++\\Sandbox\\bin\\Sandbox.exe",
    request = "launch",
    stopAtBeginningOfMainSubprogram = false,
    type = "gdb"
  },
  command = "launch",
  seq = 2,
  type = "request"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:1711 ]	"request"	{
  arguments = {
    breakpoints = { {
        line = 12
      } },
    lines = { 12 },
    source = {
      name = "HelloWorld.cpp",
      path = "D:\\Users\\Graham\\Projects\\C++\\Sandbox\\src\\HelloWorld.cpp"
    },
    sourceModified = false
  },
  command = "setBreakpoints",
  seq = 3,
  type = "request"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  command = "launch",
  request_seq = 2,
  seq = 3,
  success = true,
  type = "response"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  body = {
    breakpoint = {
      id = 1,
      verified = true
    },
    reason = "changed"
  },
  event = "breakpoint",
  seq = 4,
  type = "event"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  body = {
    breakpoint = {
      id = 1,
      verified = true
    },
    reason = "changed"
  },
  event = "breakpoint",
  seq = 5,
  type = "event"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  body = {
    breakpoints = { {
        id = 1,
        verified = true
      } }
  },
  command = "setBreakpoints",
  request_seq = 3,
  seq = 6,
  success = true,
  type = "response"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  body = {
    category = "stdout",
    output = "No source file named D:\\Users\\Graham\\Projects\\C++\\Sandbox\\src\\HelloWorld.cpp.\n"
  },
  event = "output",
  seq = 7,
  type = "event"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  body = {
    category = "stdout",
    output = "Breakpoint 1 (-source D:\\Users\\Graham\\Projects\\C++\\Sandbox\\src\\HelloWorld.cpp -line 12) pending.\n"
  },
  event = "output",
  seq = 8,
  type = "event"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:1711 ]	"request"	{
  arguments = {
    filters = {}
  },
  command = "setExceptionBreakpoints",
  seq = 4,
  type = "request"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  body = {
    breakpoints = {}
  },
  command = "setExceptionBreakpoints",
  request_seq = 4,
  seq = 9,
  success = true,
  type = "response"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:1711 ]	"request"	{
  command = "configurationDone",
  seq = 5,
  type = "request"
}
[ DEBUG ] 2024-06-10T21:09:49Z+0100 ] ...ppData/Local/nvim-data/lazy/nvim-dap/lua/dap/session.lua:966 ]	1	{
  command = "configurationDone",
  request_seq = 5,
  seq = 10,
  success = true,
  type = "response"
}

[TBPLtd]

After reading the DAP spec and the GDB manual, I now understand what is required.
Two dap configuration variables 'cwd' and 'program' were being incorrectly set.
The solution is to set 'cwd' to the directory of the executable to be debugged and to set 'program' to just the executable file name.
So for the above these would be

cwd = "D:\\Users\\Graham\\Projects\\C++\\Sandbox\\bin",
program = "Sandbox.exe",