Hi everybody and Marek (sticky password team). :-)
I've already got this offer from another website and I like your software.
I set the custom scaling level at 150% (in Control Panel\Appearance and Personalisation\Display), but in the new Windows 10 control panel - settings, system, display - it shows as 175%.
Characters seem to be too little in this way, hence my suggestion is to add some settings to modify characters size in your program...
My monitor is a Samsung SyncMaster SA100 - LS22A100NS-EN.
Current resolution is 1920x1080.
Best regards!