Although GCKit is mostly finished, it is still not well tested. It contains bugs, and possibly dragons. Do not use it. If you disregard this advice, do not file any bug reports. If you disregard this instruction, then I will point and laugh at you.
The protocols table and the class table will now grow as required. Protocols are now added to the protocols table as they are created, so you should get something sensible and introspectable back when you look up a protocol by name.
Note that concurrent resizing has not yet been implemented. That means that there is a hard limit on the number of classes that can be loaded. This is currently set to quite a small number for testing, to stress the hash table. If you're experiencing problems as a result, then please let me know and I will increase it.