RTZ savegames are not portable between v1.0 and v1.1+ versions, despite internal version being 623 for all.
V1.0 savegames are 2 bytes larger (when decompressed by gunzip) compared to v1.1+ (19064 vs. 19062 bytes for English).
Bugs of the original engine
Not Yet Fixed
The screen effect palette changes incorrectly after a PMV video [Bug #4457]
Animations in LGoP2 are incorrectly drawn above text (they should be drawn below it). An example can be seen when talking to the Indian as Lydia and performing the kiss/screw action. Also, with Barth, it can be seen from the first screen if you try and shoot Barth's spaceship: Barth will say something, and the smoke from the spaceship will be incorrectly drawn above the letters