When using SoSci Survey, please create your questions in SoSci Survey and DO NOT BUILD forms with HTML.
You can store answers from HTML forms with internal variables (see Use Custom Form Elements), but that won't work very well if a questionnaire page is shown twice. For example when you need a response check or when peple navigate back through the questionnaire. Also will the dataset be quite raw, when working with custom forms (no automatic value labels).
If you have designed your whole questionaire as HTML code, then SoSci Survey is probably not the best tool to use for data collection.