It will pool a small amount of water, but that should be of no concern… its not enough to hurt anything and most will blow off on its own when the rain stops…
I don’t run my slide in to drain it off, and never saw a need to, if its still there when I leave it will drain off at that time…
I hope you found the source of the wet slide floor… unfortunately some are built to fail with water wicking up from the bottom of the floor where the topped may or may not help…
Search for slide floor repairs by JBarca…
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