IIRC build 7000 used prerelease keys. No OEM:SLP prerelease keys known - no Loader. The Retail prerelease keys won't activate as MS' servers do not accept them, anymore. There are also no known GVLKs, no KMS, either. Doesn't look good for these builds. I guess for having an activated beta 7000 build, one would need: 1. A VM with definite hardware configuration. 2. Old, saved activation tokens matching that definite hardware. 3. VM clock pinned to the past. 4. VM offline all the time.
No, I want to avoid any problems with Yen and Admin's, so please accept the mdl forum rules. The solution is pretty easy to find by BetaArchive Team.