Try pressing the R key (as in resolution, it will change to high-res mode, which seems to be scalable).
If the game becomes slow after that, try this solution by
xenobrain:
If you change
cputype=auto
to
cputype=pentium_slow
you can start the game with all the effects such as sky and reflections enabled by default. You still need to hit "r" for high-resolution.
Finally, after a lot of experimentation checking framerate with FRAPS, I found changing
cycles=20000
to
cycles=80000
offers similar performance characteristics as the default GoG settings when running with all effects enabled and in high resolution.
The changes must be made in the dosboxMC.conf file. It's in Magic Carpet's main directory. Hope this helps!
