First step should be to just copy your entire UCCNCxxx folder to a memory stick for backup and transferring to new computer (its wise to keep a backup of your profiles/screens anyhow)
After you install UCCNC on the new computer (hopefully same version of UCCNC you had on old computer), transfer the following items from your 'backup copy' on the mem. stick to the new UCCNC folder on the new computer, and let it over-write any pre-existing files with same name:
license_xxx.txt file
profiles folder
screens folder
plugins folder
This should get you all your settings, macros, plugins, screenset, and the most important... the license file .
You can also install multiple versions of UCCNC on the same computer to run side by side, and copy the above items to new installs as well. note: There may be issues copying a profile from a very old version to a very new version of UCCNC, so take that with a grain of salt. I've not had issues, but doesn't guarantee anything
regards
Eric