Proposal uses the proposal ID at the top of the proposal right under the proposal name. Nation just uses the nation name. The format is as follows
Commend Aqualagoon /
New Ropakstadt- Code: Select all
[proposal=new_ropakstadt_1612754901]Commend Aqualagoon[/proposal] / [nation]New Ropakstadt[/nation]
Hardly anyone uses the proposal tag for proposals because it's a very short term link. Proposals disappear on the 4th day. Resolutions are not proposals and therefore no longer have the 'proposal' ID. It's probably better to just use [URL] links for both.