Hello Heryk,
Concerning your first question,
What is the equivalent of System & Institution in SP-7? Are they merged into “Global Resources”?
Yes, Global Resources in Specify 7 acts the same as System and Institution in Specify 6. Resource files under Global Resources will be used throughout the database unless there are conflicting resources at the Collection level or lower. You can learn more about the institutional hierarchy in relation to App Resources in App Resources in Specify 7.
Secondly, it is fine to have multiple form definitions at the Collection level; however, it is not recommended to have more than one form definition containing view definitions for the same table because it is unknown which view will be used.
Regarding your form definitions from Specify 7 not appearing in Specify 6, we recommend that users log out and back in after making changes to ensure they are visible in both versions. Have you tried this?