Copy the PNG with PRT-SCR then past into an application like MS PAINT
Save the PAINT image as a JPG file
In EXP go to Charts/Manage/Image and Import your jpg file using L/L points surrounding the area most important 
Not perfect but works pretty good!
Ernie

Is there some more mechanized way to do it to avoid the manual part? Let's say if I serve them from my http://localhost how can I use the MyImage feature for that? 

Ideally I'd like to see the cloud images changes along with the time slider when GRIB changes and boat moves along the track. 
 

Thanks Nick,
I manually georefernced it and ended up with this XML.  Some how <scale> element contains the date. Is it expected?

<?xml version="1.0" encoding="UTF-8"?>
<Image version="1.0" creator="Expedition - https://expeditionmarine.com">
  <size x="2500" y="1750" />
  <rev>2026-08-25T22:13:08Z</rev>
  <file>GOES18_C13_20260715_1830.png</file>
  <title>GOES18_C13_20260715_1830</title>
  <scale>2026-08-25T22:13:08Z</scale>
  <datum>WGS84</datum>
  <projection>Mercator</projection>
  <ref lat="45.000000" lon="-165.000000" x="0" y="4" />
  <ref lat="10.000000" lon="-115.000000" x="2486" y="1746" />
</Image>

> Currently, they aren't tied to the the display time.
Indeed they are, but one way only.  When I  select the image the display time jumps to date of this image. 
I realize it would be too much to ask to add the link in other direction as well :-) Also can be confusing for other sort of images.

I projected the images to EPSG:3857 and Mercator works just fine