is there any way to progress past the circus without Roxanne? ive been stuck for a while with Colleen and Ami between the lake raft, the clown, and the house basement
No, with Aimi and Colleen you'll need to go through the Lake.
Combine nails with the toy gun to help find the pump for the raft.
If you haven't found the nails, there is a black key on the table in the foyer.