Hi Benoit,
I have experienced some short of issue but not exactly the same, when we moved from 9.2 to 9.5. The issue was when we used GetROProperty("text") was getting my value in 9.2 but it was empty when we run the script in 9.5. I have tried with other property "value" and it return me the correct value. I would suggest you to narrow down your issue, by taking a single script and fix that according to 10.0, what property or method can be used in 10 when the script fails to run. I think you will definitely get a solution for it.
I have experienced some short of issue but not exactly the same, when we moved from 9.2 to 9.5. The issue was when we used GetROProperty("text") was getting my value in 9.2 but it was empty when we run the script in 9.5. I have tried with other property "value" and it return me the correct value. I would suggest you to narrow down your issue, by taking a single script and fix that according to 10.0, what property or method can be used in 10 when the script fails to run. I think you will definitely get a solution for it.