Currently it is possible to "jump" from a record in one table to View or Edit a record in another table with code like "URLRoot() & "/edit.aspx?t=" & TableId() & "&id=" & RecordId()". You place this code in a column and when it is displayed it looks exactly like a Custom Button, assuming you chose the right options.
However as it is not actually a Custom Button, it is presented differently on the screen.
Suggestion: allow this kind of functionality in the Action Call URL for Custom Buttons.
