Compound subject whose parts are joined by "and" and verb agreement : when is the singular correct? [duplicate]

I would only treat a compound subject "X and Y" as singular if it were a compound phrase that very often occurs together and which people conceptualize as a single thing. For example, I might say "this rod and reel is all tangled up", or "that mortar and pestle is for sale", or "my gin and tonic is not strong enough".

In the examples you cite here, I would consider those verbs incorrect, as far as agreement with the subject. It would be more correct to say "the information and diagram here act as a guide...", and "outdoor space and permission allow..."