Please put instructions to installation.

[XdplayerdX]

put a readme file to esplain how to put an use that in hammer.

[bliptec]

It should work just like entities declared in any other source engine game. I've never used hammer that much, but the fgd should give hammer all the information it needs.

Fair warning that this project is pretty much abandoned. On top of me not having time to continue working on it, fully-featured world portals weren't possible in gmod the last time I checked. The biggest issue being that gmod doesn't have a way to override the handling of visleafs. Matt's doors doors addon is probably more fully-featured and functional than the code here.

[XdplayerdX]

but i never used custom entities,can you say how to make this ?
yes i not found a good post of this tutorial.

[XdplayerdX]

(say how to install this and the other addon in hammer...)