There was a 1.8 release if you really want to go back....
Yes, 2.15 is a monster! Huge, bloated, and battery-hungry! (You'll notice battery consumption is 2.5X what it was under 1.7. Also your computer will occasionally complain that the device will run faster on a USB 2.0 port. Ignore it..)
The detailed map is far better! Even found, in the latest releases of VantagePoint, it will import the map from the GC, for it's own use.)
Here's a step by step.
To Add a Waypoint, if you're on the map, at the stage you've just found, click the Menu button
Scroll down 8 selections, to [Add a Waypoint].. click the joy-button
it'll give a name, distance, description, and Location menu..
Press the Joy Button twice when on the waypoint name, to edit it. (scroll to the checkmark to exit)
Scroll down to location, click the joy button
scroll down once more to Location, Then Press the Menu button scroll down 2 selections to Edit, click the joy button.
It will show your present location. scroll to the area you want to edit, click the joy button, and up/down scroll the numbers, left-right to which one to change. joy-button click inward to set the numbers once entered.
scroll down to the [OK] selection, click Back once,
Scroll down once, to select the Diskette image, and joy-button click in once to save it.
Click the back menu until you're at the main page, and go to the waypoint selection, choose the new waypoint, and then
Joy-button click on it, press Menu, It'll still be on route to the 1st stage, so cancel route, click menu again, and then click GO on the waypoint.
I know, L-O-N-G & CoNfUsInG! I learned how to do this out in the field, when tracking a Multi.. it was BONKERS!
Got annoyed with it just too many bugs and missing features from 1.7 to 2.15.
Tracks turns itself on everytime you select a geocache
no easy way to view child waypoints
battery life was about 90 minutes (this could be partly due to the tracks turning on all the time)
count does not increment
lots of missing menu items
Not outweighed by better map!
Reinstalled v1.7 from the backup I took. Simply delete all on the device and copy the files from my backup on the PC back to the device. All worked well and I now have a geocache device that works.
When you say that battery life is only about 90 mins, have you looked at the type of battery you are using, and made sure that the information on the GPS is the same? I thought battery life was short at one point, but it turns out I was using alkaline batteries, but the GPSr thought I was using lithium batteries. Mind you, when walking from cache to cache, I do put the GPSr in suspend mode.