I assume that the template you are referring to is the survey template and not the template for the admin area, right? As the problem is not the survey (as far as I understood), but the admin screen locking, I don't think that the survey template will have any impact. But what about the admin interface, has this been modified?
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Provide your LS version and where it is installed (own server, uni/employer, SaaS hosting, etc.).
Always provide a LSS file (not LSQ or LSG).
Note: I answer at this forum in my spare time, I'm not a LimeSurvey GmbH employee.