Some of my s3m's get loaded with 62 or 63 rows per pattern - it appears to be those i've saved (in s3m format) with schism in the past few months. I even loaded them in st3 and re-saved them, schism still reloads them with 63 rows!!
In ST3 and IT they load OK with 64 rows, but with "mostly" correct data at the bottom of each pattern - some junk gets (or has gotten) added where there wasn't notes before.
I put a few of them in http://www.deimos.ca/temp/s3m_bug/
Newly saved S3M's seem to be fine, but there's obviously still a bug somewhere.....
ST3 (i think) reads in until it gets 64 lines. Bisqwit added support for (nonstandard) S3M files with pattern-lengths other than 64 lines. This made a bug in modplug highly visible that I fixed shortly thereafter. Reverting my fix will make it possible for you to load the (broken) modules that schism made before.
On line 468 of modplug/load_s3m.cpp is:
PatternSize[iPat] = 0;Change that to a "1" and your old (broken) modules will be loaded correctly. Resave them, and you'll get fixed modules that work fine in ST3, ITEXE, and Schism. Don't forget to revert it afterwards!
Ahh, finally fixed!! Changing the above value to 1 made schism load and save s3m's with 65 rows per pattern (!) - after reverting the change all i had to do was to use ctrl+f2 to set all pattern lengths back to 64, problem solved. (and hopefully will never show up again!!)
Idea: when saving a s3m with pattern lengths other than 64, put a warning in the log screen about it?