Johni's not available ATM, but he checked the compatibility of the EnderIO Mod and the ReplayMod earlier today, and it worked fine, except for some GUI screens opening (which he already fixed and will be in the next release).
Try removing the mods one by one (especially such mods that alter rendering or graphics) to find out who's the culprit.
Tagging @User10 for the replay file.
@User50286 @User929
I can't reproduce the bug, neither on SP nor a local server.
However I think I have found the reason (or at least one of the reasons) for this block switching.
Could both of you try this version of the mod and check whether it solves the problem. There was an issue with recording, so your old replays will still look wrong and there's no way to fix that but new ones should look fine.
I haven't looked at any of the crashes as I'm fairly certain they are linked to the block swapping bug.