One suggestion would be to get a virtual machine with a recent version of RHEL/CentOS/whatever, and install a recent Lazarus version in it (e.g. the just released 0.9.30.4 IIRC).
You can write your application in this and test it on the old Red Hat machine.
This way, you get access to newer components, bug fixes, performance improvements etc...
There have been quite a few, so a bit of pain in the development process might save you a lot of pain in dealing with possible bugs in your compiled executables...