So I lost the demo cleaner program I downloaded from breakdown-hq before. A program that delete's all your demos exept the fastes one on each map, cpm/vq3.
It is included with defrag, I dont know if it is the exact same tool though.. Check in defrag\misc\tools\DDP-Win.zip.
It expects correctly formatted demos though, so make sure you only have demos named map[mode.phys]xx.xx.xx(name.country).dm_68. Remove all other demos and run the tool, or it will fail