Upgrade OCaml version to 4.08.x or 4.09.x
SCaml is based on OCaml 4.07.1, just because Tezos uses it. SCaml depends on a bit of Tezos code, but I think it is not difficult to compile them with newer OCaml.
The main issue is that the change of OCaml internals. I see lots of diffs in 4.09 (maybe in 4.08 too). OCaml => IML conversion should require lots of small fixes.