Packages does not execute and remains in processing mode

Dear All,

I have a incremental package which gets the max id and the max modified date which is being shown as below.

The package comes to the point which pulls the records on the basis  of the maxid and modified date and it hangs, the progress tab looks like this

The validation doesn't move ahead after the completion of the 50% and  hence package remains in the processing mode. When debugged using the breakpoints I could see that variables do get the values, but some how dataflow task hangs.

I have applied transaction on the sequence container with required and When the tasks are executed out of the container  they run just fine but hangs when they are executed inside the container. 

What could be the reason for the same?

Thanks in advance.

Thanks, Franco.