Thanks for the reply.
I was wrong about tile size, ingame the tiles are 16x16, but tiles in the file are actually 8x8 and one ingame tile is usually 4 of those together.
Another problem was however not being able to load the palette at all.
All that stuff before the actual tiles is palette data, but it only loads the first 32 bytes after the header and since they are by default mostly 00, the graphics can't be recognized at all.
Every 32 bytes from then appears to be another palette. Most tilesets use different palettes for different tiles and since I can only load 1 at a time, ripping is a bit tedious, but at least I can do it now^^
This is the debug tileset, which only uses 1 palette so I didn't have to go through the trouble of stitching it together:
The first byte appears to just define the size of the header :/ Was pretty misleading though, Tinke also recognized it as a compressed file.