A very simple and yet practical example of this limitation and a workaround is with Interface Management Profiles.
Say I have three templates (I prefix my templates with "T-")
From those three templates I build two template stacks (note that template stacks cannot have hyphens in their names, I use "TS_") and their constituent templates.
TS_ACME_User
TS_ACME_Datacenter
The "User" TS is assigned to the ficticious "User" firewall and the "Datacenter" TS to the fictitious "Datacenter" firewall.
Build an Interface Management Profile called "Ping-Only" in T-ACME-Baseline (which is a constituent T of both TS's). Build the Interface configuration in T-ACME-User and T-ACME-Datacenter.
From T-ACME-User and T-ACME-Datacenter this "Ping-Only" Interface Management Profile is not visible when building the Interfaces within these templates. However, from the Template Stacks themselves (TS_ACME_User and TS_ACME_Datacenter) "Ping-Only" is visible and can be applied.
When opening up an Interface from the Template Stack itself, the "Ping-Only" profile is present, but Panorama says the entire dialog box is Read Only and won't permit clicking OK. See screenshot below.
Lucky for us we can Override (note the Panorama Template selected is still the Template Stack).
After selecting Override the dialog box is no longer Read Only, "Ping-Only" profile is still visible, select it, click OK, Commit and Push.
Since the Override is within Panorama (and not a local firewall change), it will be unaffected by a "Force Template Values" push (good).
With that we are able to build a "Ping-Only" Interface Management Profile in a "Baseline" T, build our Interfaces in other T's, then apply the "Ping-Only" profile in the TS.
I have not tried the specific examples you mentioned in the post.
In summary, referencing a specific template's constructions directly in another template is not possible. However, constructions from a specific template can be combined with another specific template and actually applied using the Override function within the Template Stack.
