>How can I create a long string (> 255chars)?

Memory variables are limited only by available memory; if youy need a character or binary field in a table of very large size, you can use a memo field. There are known problems passing properties across method boundaries, but this can be handled by passing the data by value (wrap the property expression in parentheses in the function call) or transfer the content of the property to a memory variable, pass the variable by reference, and update the property on returning from the function or method call.