Hi - been along time.

[rich2005]

Quote:.. Where is the FLOW setting? I didn't see it as a choice in the tools when I had was using the blur tool.

Your Gimp setup does not help, you have a wide but shallow Tool Options dock. Using The smudge tool, scroll down, the flow slider is at the bottom.

AFAIK there is no Gimp blur brush, as mentioned earlier the smudge tool will paint with the foreground (FG) color when the flow setting is more than zero.

In Gimp 2.10, as well as the Gimp brush set there is the MyPaint brushes, different again. Some of these will blend, Water brushes and in the example the knife brush.

This animation with three 20 second clips https://i.imgur.com/ixd6taL.mp4
The regular smudge tool.
The smudge tool, with a small (4) flow setting, and a FG color
The MyPaint knife brush,

Quote:so there was also no ability to use blur took in PAINT mode, since I couldn't find flow.

IMHO The only way to get a good blur is make a selection and blur the selected area, but it depends what is required. You will have to experiment.