I have now tried the manifest, and it works great!
Attached are screenshots of the application running without, and with the manifest.
Funny thing is, on my Windows machine at home, it looks great in both cases, but on my Lenovo at work, it clearly looks better with the manifest.
Also, on the Lenovo, if I start Pelles Process Viewer from the Tools menu, it also looks fuzzy :-)
I will have to investigate the differences in scaling etc. on the two Windows machines, but for now the manifest does exactly what I want, and the text looks good on both machines.
Best regards.
Kenneth.