PortCoimbra has released a beta patch for Sword 2 (v4.1) to use v5.0 user interface. This isn't a v5.0 private patch obviously. It merely changes the UI without adding any new game content. The setup file basically links up to PortCoimbra server and merges a private patch for ies.ipf and ui.ipf files. See We Heard You Like UI's for details.
Hm, on a side note, I managed to call up the load replay function for v5.x clients last year. (The replay function was "hidden", but not removed, in v5.x clients. See How To Watch Replays In v5.0.) I wasn't sure if I should post it since it involved patching/replacing .ipf files. But since PortCoimbra is already releasing similar materials, maybe it doesn't matter now. Since GE-SG is updating to v6.3 soon, I might as well wait a bit.
I still need to find a place to host the files though. (File hosts that use scripts, like SendSpace and MegaUpload, don't work for this.) The hosted file must be accessible directly in the designated folder (e.g. http://www.somesite.com/myaccount/myfile.zip). Any suggestions for free web site or file host that fits the above requirement is welcomed.