RegFromApp is a simple PC monitoring tool that will show you the changes a program makes to your Registry, as they happen. It's very useful if, say, you're running a Windows tweaking tool and want to see what it's doing, or you're suspicious of a particular program and need to confirm that it's not changing any system settings.
To get started, just download and launch RegFromApp (no installation is required), then click File > Start New Process. Click Browse, navigate to and select the program you'd like to test, then click OK. It'll be launched and you can use it as normal.
As you work in your test program, though, RegFromApp will be running in the background, logging and displaying any Registry changes the program makes. Scroll down the list any time you like to see exactly what it's doing.
And when you've finished, click File > Save As to save the Registry log in Windows .REG format. If these are positive changes - Windows performance tweaks, say - then you can copy the REG files to other PCs, double-click it and the changes will be imported to their Registry, without having to install the original program.