Problem 1: Support for Trinidad tags within WTP has come fairly recently.
You may wish to try a recent WTP I-Build available from
http://download.eclipse.org/webtools/downloads/ to see if your problems
are resolved.
In general when you are dealing with pre-release Eclipse software, it is
best to ensure that you are using the same pre-requisite plugins used at
the time of that build. The update sites will only be accurate for
released software.
Problem 2: Sorry, but I can't help you on this one. This question would
be better answered on the eclipse.webtools newsgroup or an Apache Tomcat
forum.