Complex sentence: Senile Team were proud with the work done on the game however it was not fit for publishing so they expanded upon the original idea and continued working given that it was a hobby, it took Senile Team three years to finish it.
Split into simpler sentences: Senile Team were proud with the work done on the game, however, it was not fit for publishing so they expanded upon the original idea and continued working. Given that it was a hobby, it took Senile Team three years to finish it.