Any "GOTCHAs" to avoid when upgrading to TCS2015 (not subscription) from TCS4, with CC apps (subscription) in play?

So... I have to upgrade to TCS2015 (to keep in synch with a client's version of Frame) from TCS4.

I've made the purchase, downloaded the files, and am ready to install.

But...

• I want to keep TCS4 available (e.g. Frame 11 and other TCS4 products)
• I have Creative Cloud installed (subscription)
• I want to avoid any issues that may be 'out there' 🙂

Reason I'm asking is I remember back a couple versions ago, various components had to be installed/upgraded in a specific pattern to avoid problems. Also, Creative Cloud recently (5 months ago or so) pushed an update to Illustrator that was buggy (resulting in me having to reinstall earlier version (and I haven't updated the CC apps since then).

So... is there anything I need to be aware of to make this a smooth upgrade?

Any words of wisdom would be greatly appreciated!

Thanks.