Difference between MBASIC51 and 52 for CP/M?

Yes, they work fine under existing systems. I'm trying to figure out why it doesn't work on the system I'm implementing. I'm emulating the current record data in the FCB so even if a program modifies the extent or current record without a random access call, it still loads the correct sector from the file. So far, it works with WordStar 3. I'm still implementing write support. I've compared my emulated FCB to the one generated by a CP/M system and from what I can tell, the CR/EX/S2 data is the same. I've had a look at the CP/M source, I don't see anything unusual there. Really, the only thing that's different is the allocation data. I'm following the CP/M-86 convention for converting between FAT file system data and CP/M FCB's. It's documented here: http://www.seasip.info/Cpm/dosplus_fat.html Knowing me, it's something silly or trivial, but until I find it... :)