I'm sorry to hear you're having trouble with Tableau 6.0. Please e-mail customer support so that they can work with you to securely request your log files and if possible your workbook(s). Additionally please always upload your crash reports to Tableau when prompted so that we can examine them for the location of the crash.
I am building a dashboard where I actually want to take a bit more control of how space is used on the screen: therefore I create text boxes and cells (sheets with 1 value) that I arrange along with a map and a filter action.
The software has crashed a couple of times while I was trying to build the dashboard.
Still, I am far of the 130 sheets: I barely hit the 30 when it crashed, with a reasonnable single-sheet excel Data source (300Rows X 40 Col.)
Further than this, I am also wondering whether the way to build my dashboard is right.
Is there any way to link single-cell elements to data dependent on a filter action? (like in other dashboard software)
As for the crashing while editing a dashboard, if you are using 6.0.6, contact Tableau support - firstname.lastname@example.org , I believe they have a fix for this situation.
As for your other question, can you provide a sample workbook that demonstrates your situation?