The parts in question are not sharp in the images, so I am speculating.

1) the brown spot in the second image appears granular, some moths lay clusters of eggs most anywhere.

2) some paper or mud wasps do small "false starts" on their nests and just quit after a little blob is deposited. In this case, the working wasps would be obvious.

Here's the latest. I went out this morning to see if I could get better shots. We are very rural and it's entirely possible that these were around last year, possibly on our house, etc. without us noticing. The porch is new and you can really notice them against the white. The second and third shots are of the same spot. The second was this morning, the third this afternoon. The first shot is a different spot.

1 and 2 are moth eggs--see the babies coming out in #2? Awwwwww cute but what a silly spot for eggs. They're gonna starve.

#3 is something different I think. Possibly eggs too, of course.

2 and 3 are the same spot. 2 being early morning, 3 being later in the day. Moths or the like, I can handle, as long as it's not termites.