Do you have J-channel around the window? If so, is there a seam that's not 'sealed'?
You could 'lift' the bottom-most sheet of vinyl to take a look behind the sheet. And from there, you can lift out other sheets and follow the leak. Who knows where it's coming from.
You'll need a Tuck Tool to unclasp the sheets from each other. Visit the Home Center and ask for one in the Building Materials Dept. My best to ya and hope this helps.
Jay J -Moderator
PS: Once you've found where the water stains start, you'll need to make a fix. Since 'we' don't know where it is, we'll have to wait until you get back to us. If it's too long, start a NEW thread ...
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