My problem is the following, in Mekanism 1.7.10 version 7.1.1.97, I crafted the Free Runners, and after charging them I noticed that they are absorbing fall damage without any problem yet they fail at stepping up one high blocks like they should and that is the main reason I crafted them.

The free runners also don't appear on my character, as if I wasn't wearing them.

I checked Google and here but couldn't find an answer to my problem, I hope someone can help me out.

Thank you in advance.

I have a feeling that this is a purely SMP issue, but I would recommend updating Mekanism to the latest version. I can't reproduce this on my end.