Using 0.7.5a, randomly i can't move the player(but i can break block and interact with the world). Only way to solve is by switching to creative, close the world, reopen it but after some variable time(generally a short period) it stops again. I think it depends on dynamictrees because using the same allthemods 3 modified profile without dynamictrees in another world, this doesn't happen. I have the Bop addon too.

That's bizarre. I can't think of why this would be happening. It doesn't sound like lag. I need to reproduce this so I guess we should start by having you list the mods you use.

Are you in leaves by chance? Could you send a screenshot of it happening?

No, It happens even inside caves. There aren't any strange things happening, apart the fact that i can't walk(but i can move the visual, i can even break blocks within range)

https://imgur.com/a/jRDzZ this is the mod list

Oh dear.

I know, there are lot of mods haha

I think i know a way to replicate the bug, it happens most of the times when you're in a cave few blocks under a dynamic tree. to get around: switch to creative while stucked, close the game, reopen(journeymap will create a death waypoint but you don't lose stuff, i don't know if it can be useful as information) and switch back to survival and you'll be able to move again. when stucked you can't open the inventory.

Unable to replicate. For this issue it is up to the poster to determine which mod is interacting badly. When it is found resubmit a new issue citing the specific mod compatibility problem.