How to edit the appearance of a FreeArc sfx archive?

[Newbie]

I want to change sfx interface a little.

If sfx is created with free arc I will get this message with Resource Hacker



If I create sfx with Winrar, all is fine then.

I can change/modify sfx without any problem.

But I would like to use Free arc, why, logical reason, compression is way better.

Anyone knows what to do.

Thanks

EDIT:

But it seems all is fine with alpha version, somehow I've downloaded 0.66 instead of 0.67

Will check it out and report back.