If the exe is running in the same folder as the DBA file, then it may be down to the exe running a little faster.
In your program, anywhere you have a Get Image command, try putting a Wait 1 on the next line - especially if the next line uses the image you just grabbed.
My theory is that in a compiled program, the line following the Get Image is executed before the Get Image has completed - the result is that the image is not yet available for the next line. This then throws up the Bitmap Does Not Exist error.
This may be rubbish, but it's only a theory. All you can do is try it and see if it fixes your problem.
If it does, you can then join me in theorising exactly what is happening...
TDK_Man