I suppose that's a fair comment molgrips...it's just not really my cup of tea. Anyway, back to the OP...
If you're floating the floor and doing it yourself, it might be worth trying something like this. It's a very sticky underlay to which the floor sticks under the bottom. I've never used it myself, but have heard good reports. I tend to go the extra mile and use a wood-flooring specific adhesive but they're not cheap, and with due respect, gluing a floor to a concrete floor is not always a job for the amateur...it can get very messy, and as I assume the bamboo flooring is already finished with a lacquer, it's not like you've got a full sanding to remove the glue that will get everywhere (not like I'd ever be messy
).
Gluing on the tongue and grooves is also an option, but you get no adherence through the bottom of the boards (which is what you should have) and the floor can end up feeling a little too springy. Also, instead of using a polythene layer for a DPM, consider buying a roller-on liquid DPM (two part, pricier but one coat only and quick cure time; one-part, cheaper, two coats at least and probably longer cure time) - easier to do and an all round better solution.
Feel free to e-mail me off forum if you have any further questions.
darcyciaran [at] mac [dot] com