[Need help with modpack and mod.]

So, I hope you could help me out. So I have a modpack, I use it only to play with friends, nothing more. but I wanted to ask if there is any way to optimize it to the max (specialy a server)? I have already installed optifine.

Also, I would like to know how is the mod called which adds electric engines to buildcraft wich works from electricity produced from IC2. I can remember there was one in very old technic pack.

[Problem with recording game using Mirillis]

I don't know how to bump my thread so I'm just gonna do it this way...

[Problem with recording game using Mirillis]

So, I have a problem with Tekkit Lite. I can't record it. When I open up my Mirillis program and Tekkit Lite I can record only in small window if i try to maximize window or go into fullscreen mode java crashes. I get message that Java stoped responding. I would be really greatfull if you could help me . Thanks in advance