The DimPro help is a html file within the DimPro folder. I have a hard copy, but it came with the boxed synth.
Rapture and DimPro are similiar, but not exactly. DimPro will play back a sample if it is longer than 3000 samples - Rapture will always make a wavetable of the sample no matter what the legnth. This wavetable ain't the PPG kind, but a calculated file that plays cleanly from low to high notes. Rapture has some different goodies, tho, like step sequencers. They also come w/ different sample-sets - DimPro is more geared for acoustic instruments while Rapture gyrates toward more electronic and synth sounds. You can use the samples and SFZ files from one in the other, but the programs won't work w/ each others because of different aspects of the programs.
Usually I use DimPro for acoustic instruments and longer, more evolving sounds (playing back an entire sample helps w/ this), while Rapture is used for more synthy sounds (esp. with the sequencers). They each have their place, tho it would be nice if one program combined both their stregnths. Prehaps this is what Cake will do with their next iteration, although it has been so long I'm hoping for more than just a mash of the two.
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