Even it sounds about own way of customizing, I guess it should be allowed by freebitco.in.
Because, I remember that @TheQuin once stated that making use of any bots is NOT allowed as per their TOS (I am sorry I could not locate such a post right away to link here).
But I remember people were explicitly selling auto click bots for claiming freerolls of freebitco.in some years back on this forum itself. I guess it would be like if you own only one account and if you use bots then they might be allowing you but if you try abusing them with multiple accounts with bots then they will ban all of your accounts; still it is just my assumptions on bot usage in freebitco.in which is based on few crypto gambling houses are allowing multiple accounts with them until not abusing their bonus program.