If you have a lot of data in other files it is possible to greatly accelarate the process of building a model.
You can use diagrams from other models
You can import pictures from other programs
You can import lists to create the symbols on a diagram.
For example, you have an equipment list in Excel. Then go through the list in Excel to get just the items you want in the model.
Then sort the rows into the different types of equipment. Then copy each set of the same equipment type from the spreadsheet and use paste special , selecting an appropriate symbol to import each type as.
Then you can move the symbols onto the various diagrams
Don't worry about getting it right first time, you can easily rearrange the model at any time.
For example, you can :
Change objects including their classes, links, appearance etc using Copy and Paste Object Properties
Move objects to other Diagrams
Change Diagram classes
Tips - Use Model Review to check your model without having to look at each diagram
Frequently use Database Build and see if the results make sense