I am only really familiar with zone 4 or colder plants, but if you have shade or part shade, periwinkle (Vinca minor) is a vine that blooms in spring. An easy, evergreen perennial. Don't confuse this with the "annual" vinca vine that you see in flowering containers. They are related, but not the same. If you have part sun to full sun, the many types of creeping sedums will fit the bill.

Other than that, I can't think of anything except, well, if you have acid soil, there is kinnik-kinnik (Arctostaphylos uva-ursi), but the flowers are small, cute but not showy. But it does have red berries. Flowing between rocks, definitely, but over them is questionable. Candytuft (Iberis sempervirens)isn't picky about soil acidity or alkalinity, is a good showy, flowing between rocks perennial, but again not over rocks. Both plants are evergreen.

Rick

I do have two types of vinca that were located in spots that eluded my massive renovation, one variegated and one regular. I also have some really nice ajuga interspersed. I did have a 4X6' mat of lithadora that was not quite so fortunate.

I was actually thinking of both kinnik-kinnik and candytuft sempervirens as well as armeria girardi,arabis, aethionema, and alyssum. I have pleny of cracks and crevices that need color and texture. We have had this mother hen in the front yard for years that has helped fill many of these already.

The lithadora actually trailed nicely and I might try a couple of different colors of that to trail. I was even thinking about trying some cotoneaster dammeri or some euonymus fortenei but I'm not quite sure if either is right for the job.

I think I am prejudice. I just don't like Euonymus fortunei. It is so rigid, with sprigs sticking up here and there, certainly not a plant soothing to the soul, or graceful. All that and the foliage is just so so. If you can deal with evergreens that don't flower, any spreading juniper or Russian cypress(Microbiota decussata) will be more graceful, more interesting, softer looking, and flow over rocks too.

Everything you mentioned are good opportunities. (I am not familiar with lithodora.) And remember any plant can grow between rocks.

I planted lithodora last year and it was beautiful.
It is now mid April and I don't see much life to this plant.
Is it hardy to Zone 5? or will I have to replace it.

Thank you.