pygame-text-input | small module that enables you to input text

Your third problem (truncated pickle data) is because you are using TCP, and you are unpickling whatever recv returns. You might be thinking that whenever you send something, and the receiver calls recv, returns the exact same thing, but actually it doesn't. TCP splits your data up into packets, so the receiver might not receive all the data at the same time.

For example, if you send "abcdefgh" and then separately send "ijkl", it's allowed for the first receive to return "abcd" and the second to return "efghijkl". Or the first one could return "ab" and the second one could return "cde" and the third one could return "fghijkl", or so on.

You have to design a way for the receiver to know when to stop receiving. For example, if you sent "8abcdefgh" and then "4ijkl", the receiver could get "8abcdefgh4ij", and then it knows "8abcdefgh" is one "send" (because it starts with 8 and then 8 more bytes) and it knows the "4ij" is the beginning of the next "send" but it's not the whole thing (because it starts with 4 but there aren't 4 more bytes).

Another way is to send a special character like a newline (enter key) after each message. This probably doesn't work with pickles because pickles can have newlines in them. But you could choose another byte that pickles don't have, like 0xFF. Then the receiver knows to keep on receiving until it sees the byte 0xFF.