Regarding Xnet properties getting lost

Hi,

  I am currently using 15.7 Allegro PCB Design XL.

I have assigned Models to components to assign XNET properties.

Whenever iam importing the latest netlist the Xnet properties are getting lost.

Our schematic engineers are using Mentor Dx Designer to generate netlist in .tel format.

Every time I import netlist i set the path for device files and import the .tel.

After importing netlist all the xnet properties are getting lost .Iam not selecting the "remove rules" check box.

Even then rules are getting over written.

Can you please suggest  and also I have one more issue.

Whenever I am changing the board file name is getting changed or when i am sharing the .brd file with any of my collegues the Models are getting lost and thenit is throwing DRC's when DB DOCTOR is Run.

I have tried Saving the models in .dat format and loading some times it works and some times it wont.

I have tried retaining the same .dml and .iml in the same folder even it did not work.

Can you please suggest the possible problem and its solution .

 It is  so painful to set the models for every netin.

Awaiting your help.

Rgds,

Sarath