It's not a Win7 issue.
But an MPASMWIN issue.

If you go to Start > Microchip > MPLAB IDE v8.43 > MPASMWIN
You'll see the same DOS window pop-up. (but you get the GUI too).
It does the same thing with WinXP.

I don't know why it takes so long either.
If you compile the ASM directly with MPASMWIN, it doesn't take nearly as long.

If it's to be solved within MCS, I think David Barker has to do it.

MPASMWIN has no problems from within MPLAB or Proteus. Still nice and fast, and no pop-ups.
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