Re: Concrete curbing
Concrete doesn't work like that, unfortunately. Even if it did, you'd end up with blotchy, nasty looking curb work. I recommend removing the damaged sections and repouring them. You can form it easily enough and use a removed piece to make a template pattern for the screed block. If that doesn't sound like something you can do, then you'll need to call a few landscapers for quotes on replacing the damaged sections.
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!