Using the newest version, 182, the step assist doesn't work when when you change dimensions still, but their speed boost works though.

6b0b158 didn't fixed it?

Could it be because I'm still on forge 1291?

It did not it seems. I just did a test with only botania installed and I swapped dimensions and I only receive the speed boost and have to re-equip it to get the step assist.

There must be some incompatibility with the Aether mod, since it still doesnt work when you have this mod. It worked nicely before you changed it initially