Make sure you actually downloaded reuploaded build by checking MD5 (d089d0de3cd76cb063b06fc000087c54) or SHA1 (f6b5e711475355580b219a12ce1c079f648edd87) checksum. Sourceforge sometimes caches old builds.
You "can" unlock your phone, but in case of CN versions you must have Xiaomi Account with China region and Chinese Xiaomi Community permissions, which require ID verification and pass an exam. No go for most Global users.
1. Xiaomi checks them differently in Global ROM (and our ROM is being recognized in code as Global ROM). Patched for next release.
2. "ability to customize them" - explain, no idea what do you mean there.
It doesn't matter. You are NOT supposed to update system launcher (and any other Xiaomi's system APK in our ROM).
Official system launcher tries to find Global App vault. We use Chinese App vault.