I do not have much on the Urech line since it is not in my direct line. Years ago two of the Urech girls married into my family.
I am away from home until the middle of April and do not have internet service where we are staying and only get home every other weekend making little time for research.
I know that there was a book written on Rudolf Urech's descendants which was well documented which may help you.I am sorry to say I do not have a copy of this book.When we return home I will see if one of the ladies that descends from this line and has a book will correspond with you.She lives in Houston, but her computer died and she only uses the library computer now and sometimes it is a long time in hearing from her.
If you have not heard from me by the 20th of April email me or post here and I will see what I can do to help.