[Tycho]

By memory, because I'm not at home now.

.clg = captain log

.crp = crew report panel or console report panel

.isf = ??

.map = drawings on map

.psc = player submarine control or cfg or something

.rmr = radio messages received

.rms = radio messages send

.rsf = ?? probably something for replays, function that is not finished , and don't work.

.sav = ?? save


.clg, .crp, .map, .psc, .rmr, .rms - are text files, you can open and edit these with notepad.

.sav was somehow encrypted, you can open it with hex editor, disassembler, debugger....