Yes. To quote LIDS co-author Philippe Biondi:
"LIDS works on top of the VFS layer, so that it can handle every fs linux supports."
There have been problems reported with SMP systems running LIDS. Many of the problems have been fixed, so it is recommended that you try out the latest version and see for yourself. Xie and Philippe are very dedicated to fixing any such problems, so please make sure to report any to the LIDS mailing list.
Yes. If you apply both the LIDS and Openwall patches yourself, one of the hunks will fail (as of release 0.9.11 for kernel 2.2.18). It is a minor error that won't affect your system security. However, if you don't like the error, you can visit http://root-it.be/community/lids and download the combined LIDS + Openwall patch. Wim Vandersmissen was nice enough to combine the patches and fix the error for us. Wim also offers several other combo patches on his site that include LIDS.
I'm not aware of any confirmed success stories on other hardware platforms. If you get LIDS to work on another architecture, be sure to let everyone know of your efforts
LIDS 0.9.x is for the 2.2.x Linux kernel, and LIDS 1.0.x is for the 2.4.x Linux kernel.