Trigger to Execute Automatic Dimension Update Package

Dear BPC Experts,

This question may not be directly related with BPC, but I am sure some of you might have faced this question by client.

I am working on BPC 7.5 MS and the data base is SQL 2008

My Client has asked me to design a SSIS package to automate Dimension Update processes. The first step is create a trigger that would execute the package. This trigger has to be designed on data source file (i.e. flat file) so that it can track the changes & execute the 'Automate Dimension update package'. I suggested following option to client to design the trigger, but non of them is acceptable to client and they are looking for a .cmd file based trigger

Suggestion 1- Use 'File Watcher Task' in control flow of package. This task will trigger all changes in file - Not acceptable to client

Suggestion 2 - Build a query on change data and then design a package on this query with T-SQL Script to assign data to respective dimension - Not acceptable to client

Client want me to design a trigger based on .cmd file. Now I am not familiar with .cmd file. Kindly guide me on following

1 - What is .cmd file.

2 - What script/command I need to write to trigger the package

3 - Where do in need to save this file

4 - Any additional information required for me to complete this task.

Regards,

Rahul