My brother-in-law used the same product & had used it once before,said the only problem he had is if you drive in with wet tire the product will lift!!
I plan on at some time doing my garage floor & after researching found that you should not wash the floor, it should be ground with a concert grinder than vacuumed off, & to use a product that is used by professionals. Can be brought through Versatile Building Products !
Hope your coating holds up, looks good!