You want to branch to another survey and continue from where you've left? I don't remember when it was added but there is a sys_skipto parameter in URL link parameters. Haven't used it, but help file states:
"...If you want to restart an SSI Web questionnaire and skip to ("link to") a specific question name, you can do so by including a "sys_skipto" variable within the URL hyperlink (note: only works for restarts). For example:
The hyperlink above restarts the tep1 survey and skips respondents directly to Q11.
The most common use for this functionality is for linking multiple surveys (such as multiple conjoint modules) while still maintaining quota control. For example, consider the following study design:
Study1 (CiW-type survey)
· Study2 (CBC survey #1)
· Study3 (CBC survey #2)
All respondents start in Study1 and complete Q1-Q10. After Q10, respondents receive either Study2 or Study3, depending on answers within Study1. After completing the CBC section, respondents return to Study1 to complete the survey (Q11-Q20) and be counted toward the quotas that are maintained in Study1.
To do this, a skip pattern is inserted within Study1 that skips respondents from Q10 to one of two Terminate/Link questions placed in Study1. The Terminate/Link questions mark respondents as incomplete, and link them to either Study2 or Study3. Then, at the end of Study2 and Study3, Terminate/Link questions link respondents back to Study1, with sys_skipto=Q11 placed within the URL. Respondents finish Q11-Q20 and reach a Terminate/Link question in Study1 that marks respondents as complete.
Note: if restarting a survey and skipping forward within the questionnaire, make sure not to set passthrough variables to new values. If a passthrough variable has already been stored and is later resubmitted as a different value, the original value is maintained. "