Have you considered (electro-)magnetic forces?
My first thought was that if the colonists had something magnetic on them, they could be pulled toward the surface by electromagnets, for which I have three working ideas:
A non-toxic compound that can be magnetically attracted is spread through their body, much like some elements that are used forensically to identify where someone grew up and get in our system through the food chain but aren't there for any specific purpose. This might even already exist, though we probably don't like putting weird stuff inside us and wasting a lot of energy to create artificial forces for such purposes. This has the great advantage that by spreading evenly through the body we'd perceive gravity perfectly fine (as it would also be in the instruments near our ears that tell us which way is up, a set of three canals per ear filled with a liquid if I'm not mistaken)
Metallic implants, spread across the body, this would probably not give us the complete feeling of gravity unless we also tampered with the canals in the ears. Should be doable, though maybe not very comfortable
Suits with metal woven into them. This would give us a much more even distribution of the forces than implants at regular intervals, and we could again modify the ear canals. These also have the advantage of being adjustable to different conditions, either by just swapping them for another suite in a different environment, or by even being powered and creating small electromagnetic fields themselves. This would also allow them to respond to the following issue:
Other than losing power to the electric field, which would essentially bring you back to microgravity, a far more powerful electric field would equate to bone-crushing gravity, and that would, in fact, be a very interesting hack I'd like to see in a story some day.
An other point is that if you make the implants smaller and compensate by increasing the number, if you keep going you'll end up with the first solution.
Then I remembered a passage from a book I started reading (or rather, hearing, as an audiobook) a while ago, here's what I remember, maybe someone else can correct anything I got wrong. I think I came across this one in Michio Kaku's Physics of the Impossible, where he theorizes on ways to implement some sci-fi ideas in the (not particularly) near future, based on what we know.
The author was saying that sufficiently large electrical fields would manage to magnetize (not sure it's the right term) a lot more than the usual metals, and this would allow artificial gravity. More specifically I believe he was referring to levitation, actually lifting us off the ground. This would require enormous amounts of energy, and would possibly affect us in other ways, but maybe fusion reactors would permit it.
On a side note, I should note that you can get electronics to work under extreme magnetic forces, and it would be conceivable that they are all manufactured so (fluctuations would be more of a problem but they'd be a problem for humans too with my solutions so presumably there won't be any). So this should not stand in the way of the rest of your tech.