Do you know programs to edit the game Lemmings 95?
No, someone will have to write one. It seems at this point 0xdeadbeef knows the most about the Windows version.
- The digging mask of the miner isn't correct (looks not like the stairs made by a builder, the steps that are dug are not correct).
Interesting. I find the same is true in the SNES version (but I don't know whether it's incorrect in the same way as Windows). The Amiga version does have a builder-staircase-like mining mask.
- Some sounds aren't playing or aren't good (e.g: Lemmings falling at the bottom of the level, "Oh no!" before exploding (the lemmings only said "Oh no!" when it explode, this is ugly!
What else should it do? In the Amiga version it says "Oh no" too! In fact, the only reason the DOS version doesn't say "Oh no" is because of limitations of sound hardware for PCs of that time, so it attempts to create a poor imitation of "Oh no" via pitch-bended music notes.
The Lemmings falling off the bottom of the level (the "Ahhh" screaming sound effect) is missing in the DOS version as well.
Of course, in the windows version they should all be just .wav files, so changing the existing sound effects should be trivial. Adding new ones probably much messier to do though.
- When assigning a skill to a lemming, it starts the skill just one pixel in front, a little bit in front where it is supposed to be.
I'm not sure what you mean. It seems to me that in the DOS version something similar sometimes happens. It's possible that the game only deals with skill assignments after it first updates the position of the Lemming. Lemmings 1 in general just isn't exactly very user-friendly when it comes to doing pixel-precise moves.
- Edit the graphics (open the .spr and .dat files) using the correct palettes (*.pal)
0xdeadbeef would know the most, followed by Mindless. I'm too lazy to care.
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Perhaps it'd be easier if you wait for 0xdeadbeef to finish his Java version of Lemmings. It's much easier to fix or improve things when the source code and the human programmer is still available.