Also, the best way to be sure your client likes the way the site is setup, is to first provide them with either screenshots or links to the site as it is with how it is exported when RLM exports it ... "before" ... you do any changes to the code at all.
Create yourself a custom.css file and put it in a separate folder. I found doing the separate folder for the custom css helps so it doesn't get deleted when you replace with the new RLM code as many times I like to just delete all the files outright and put the new ones in rather than overwriting them. I named that folder custom-css , classy right? hahaha.
Anyways, make your changes in a custom.css file that you need to make to the main code by copying that code you need into the custom.css file. This way you won't have to lose those changes upon re-exporting as Steve mentioned.
Then show the site as you're editing the custom css file, don't make major changes to the actual files until your client says they are satisfied with the Layout (how things are positioned and sized for the most part) first. This way, the only thing you're changing is the content and since most of that is done within RLM as well (textually anyways), there won't be much they will want to change later that will make you have to start over in RLM with the layout without the changes done.
Be sure to link your custom.css file within RLM as well. It gives you that ability and that makes it much easier to see your changes as you go as well without having to wait for export.