think i may be getting round it. ill explain but might get a bit complicated (!)
i tried bidding for a player in the 1st week and it froze. so next time i didnt bid for anyone first week, and put 2 players up for sale (who then were sold), and it let me carry on to the next week, where i bidded for and bought a player and it didnt freeze. i then pushed my luck the next week and tried bidding for another player and it froze. so back to square one!
v.odd cause im nowhere near my squad limit so cant have been wanting me to get rid before i bought i dont think.
maybe it is just a dodgy bit of the game like you say. might just depend on luck whether it lets you carry on after bidding for players.