Apptio for All

I didn't even know there existed something called Apex Design & Navigation, @Heather stewart 😮😮😮​​
What I'd do is creating a landing page in CT (my main area of expertise) with buttons linked to the specific URLs, even pointing to other Apptio modules.
We have done it for report collections inside CT and it works well:

See that we have replaced most of Apptio's OOTB reports with our own set. I haven't tested it, but I guess it would work if I had other non-CT URLs.

It definitely works with HTML components: we have created a master report that looks like this:

• The Contact the TBM Office hyperlink opens the default mail client with a few fields thrown in
• The TPE Cost Model Documentation link takes the user to our database of how-to articles
• We have replicated Apptio's home button to return to the above landing page