Actually it's not the GUI that causes the issue, but having many bots running at once does increase CPU load. How many bots are we talking about here?

Talking to the guys here we just came up with an idea about how we can reduce the load. We will add an update as soon as possible.
Thanks for your continued support!
All the best
Jonathan
Uhm.... I have 7 bots running all of the same time hehe!

I believe the runtime error has something to do with the CPU usage as well.

What runtime error?! Tell me more please...