PDF Expert DAte ISsue
A couple of Quick Notes as I am working on this issue as well.
1) Adobe via Live Cycle has its own scripting lanque "FormCalc" you need to make sure your actually using Java Script for things to have any chance at working
2) Save your form as a STATIC PDF a Live Cyce Dynamics Forms are not spported
3) PDF Expert is by far the best PDF viewer out there, but remember iOS and/or PDF Expert may not support every last Java command out there for example the "Z" date format will display UTC time perfectly on your desktop running Acrobat Reader but will not display in PDF Expert. Likewise some callss for "postSUBMIT" actons are not fully supported
Quick Work Around:
Create your form using Acrobat Pro which if you have life cycle you probably also have this and then you can set actions to run when a submit button is clicked
like: getField("timestamp").value = (new Date()).toString(); which will set the value of the field "timestamp" to the GMT Local Time
BTW PDF Expert support is very helpful, they provided the above script to resolve issues I was having in timestamping forms before email submission
Hope this Helps
PS Let me kno if you get it figured out in Live Cycle it would make forms SOooooo much easier