|Bugs concerning edeting in Legacy.|
Intersecting 3d floors: If you have the same sector heights of 2 3d floors and assign them to the same sector Legacy will crash quite merciless. So if you have Legacy instantly crash when you look into a area with 3d floors.. This is most likely the cause.
Dancing Lines: This is a bug that's inherited from the original Doom, When walking along a linedef in Legacy it'll dance back and forth. This is due to a bug in the rendering code and it's apparent like this in almost all Doom ports that feature looking up and down. (Not in zDoom, and Hardware ports)
HOM textures: Legacys translucent textures are not working in Harware mode. They are in the process of being implented. At the present they are presenting a HOM like effect, instead of translucency.
Missing Doomguy: Not a bug per se. But Legacy have for some weird reason a limit of 1 Doomguy per map. This meaning that hacx such as used in Dystopia3 and Vrack2 don't work in Legacy.