This is a bug that has plagued me since I started using DosBox many versions ago. I'm running Dune 2, (happens in other games as well), I click to build something. The unit begins producing and is immediately put on hold as if I clicked twice. Hmm. Odd. This happens sometimes and other times not. Strange. So I play around a little. If I click while the cursor is holding a fixed position this problem does not happen. If I click while moving the mouse, I might get a double click. If I click while moving the mouse really fast I can get a triple or quad and maybe even quint click all from pressing the button only once. I've played a lot with the mouse sensitivity and it has not fixed the problem at all. Please let me know if this is known and being worked on. I'm on an optical, USB mouse. (wouldn't expect that to matter though)
-Jim