[Limdep Nlogit List] Selection with Bivariate probit

[rhythm Em]

Dear all,

My data and variable suggests that my model is bivariate probit with selection. I put " ; selection " on my bivariate model. I wonder, rho became non-significant with pretty high standard error which was significant in case of simple bivariate probit setting. My rho in selection model has value of around 0.95 though. I have included ";robust" option in both cases. In my model, I also need to account for weighting and i have included " ;WTS=...." . I just surprised why the SE in bivariate selection is coming so big making row non-significant. 

LR test with null (row=0) have value of around 56. That means it rejects null. Therefore, I have so dilema in using single probit or bivariate. 
Does just the option ";selection" account for selection model? or I need to add something more? Also, it may woth mentioning that I have around 1800 observations. Would you please suggest me to handle my situation.

I would appreciate your response as soon as possible. Thanks.

Sincerely,
Rhythm