EduSystem questions

It was written.... Being as I'm so enamored with timesharing systems, especially basic oriented ones... I'd like to see about getting EduSystem up on my 8E. I skimmed through the Edusystem handbook and find some information unclear. 1) It appears that for all versions of EduSystem, the Timesharing Extension board isn't required. So what OS's DID use the timesharing extension board? More importantly can someone confirm that no edusystem versions require this board? 2) The edusystem handbook is a bit unclear with regards to disk drive support in edusystem-25. At the beginning of the section they say an RK05 can be used in place of dectape, but no mention is made of that anywhere else in that section. In addition, the mention of a disk drive at the beginning of the -20 section is crossed out along with a delete mark. So what's the deal? Can you save program files to hard disk on edusystem-25? And most importantly, in skimming through the capabilities in the handbook, Edusystem-50 looks MOST impressive. It does something my beloved HP/TSB does not, and that is allow other languages (focal, fortran, and assembler) to be used in addition to basic (apparently) DURING timesharing. So my obvious next question is, does anyone have a installable copy of Edusystem-50?? I may go the RSTS/E route on my 11/45, but will probably do RT-11/TSX+ instead. But on the 8E, Edusystem-50 looks quite nice. Any advice is most appreciated! Jay West