Unfortunately, no, the CM-32P is not MT-32 compatible. The CM (Computer Music) line of modules are basically other Roland synths repackaged especially for desktop computer use, housed in white cases and without any front panel controls or display beyond a volume knob. The nomenclature of the CM line is a bit confusing.
The CM-32P is equivalent to a Roland U-110. The 'P' stands for PCM synthesis, the technology that the U-110 used. The U-110 and consequently the CM-32P have pretty much no use for games, but it is a nice sounding older module in its own right, for someone interested in synths and composition in general. Sounds are fewer than the SC-55 but arguably better in some instances, and there are a series of add-on cards, if you can find them, to provide additional sounds.
The 'L' in CM-32L, on the other hand, stands for Linear Arithmetic synthesis, the technology of the MT-32. It also has a few extra sound effects that the MT-32 lacks, so technically speaking it's more properly equivalent to the LAPC-I, but at any rate it is MT-32 compatible.
The CM-32P and CM-32L were also combined into a single module featuring both synthesis technologies called the CM-64. This is also MT-32 compatible, of course, though solely by virtue of its CM-32L half.
Hope this helps. For a little more info, you can look here:http://www.synthony.com/vintage/cm32l32p64.html
There's also a wonderful list somewhere on the Internet with detailed specs on pretty much every Roland synth, but I've misplaced the link and I'm afraid I don't have time to track it down at the moment.