I know DO12 is the beta answer, but is it possible to use an external manifest file and the PreferExternalManifest registry key to help solve the HI DPI issue with DO11? This is how Eclipse Mars users can fix their IDE. See https://community.perfectomobile.com/posts/1135007-solution-for-eclipse-with-high-resolution-laptops for the example for Eclipse.
I'm just not sure I want to go the beta route yet.
Which issue(s) are you trying to solve?
A manifest probably won't be the answer but changing font sizes can be done within Preferences if fonts are the problem.
The icons are incredibly small on my Lenovo Yoga 900. It's a 3200x1800 display, and Windows is set at the recommended setting of 250%.
The technique in that link solves the same problem for Eclipse Mars. Eclipse Neon comes with a fix built-in.
Just thought I'd see if there was something similar possible.
File and folder icons should come from the system and use the system size.
But I am guessing you mean the toolbar icons. In Opus 11, toolbar icons can be swapped for a larger icon set. (One example "XL" set / another example.)
One thing you can't change are some of the icons used in dialogs (e.g. parts of Preferences) and the status bar format lock and things like that which aren't on toolbars or using the toolbar icon set.
In Opus 12, high DPI icons and (when it makes sense) icon DPI scaling are built into the program so everything is automatic, including using the same configuration across multiple DPIs. (Less obvious things like stored window positions are also handled in a way which considers the DPI of both when they were saved and when they are loaded.)
The Opus 12 betas are very stable now so I would recommend switching to them if you're using high DPI and want the easiest path, but Opus 11 is livable in high DPI with a little configuration.