No, there is no restriction in using variables on different pages. To pipe in the response to the previous question into the following question, click Insert Variable and select the question for which you wish to add a follow-up question. Read more here. However, you might find custom variables not working well if you are testing the survey in Preview mode. In Preview mode, we don't save the answers to pipe into the next pages. So, make sure you publish the survey to make use of this feature.