In singleplayer, the raft float works as expected, albeit always placed as a black one rather than its intended color (or at least not orange). However, on a server, when placing a float, the float entity itself floats around on the water as expected, however when interacted with by a player, it crashes the server (crash report here)

The entity forever corrupts the world, crashing the server any time any player gets near the float entity. This forces the world to be loaded without the mod and re-loading the mod afterwards (and, of course, having to regain lost items).

Alright so an additional note: if you download the world from the server in singleplayer, you can load in just fine with the raft and destroy it, so not all is lost.