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Your LimeSurvey version: [see right hand bottom of your LimeSurvey admin screen] 5.3.11
Own server or LimeSurvey hosting: LimeSurvey hosting
Survey theme/template: modified fruity
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I am a relatively new user of LimeSurvey.  I created a draft version of a questionnaire for review and got several comments requiring revisions.  There were two questions that used simple logic (eg, if Q41=yes, then display Q42).  I copied the draft version and made the changes; these were all to question text - no logic changes.  The new copy had scrambled the order of the questions using logic.  The questions incorporating the logic were moved ahead of the initial question.  Any ideas?  Thanks.

Looks like a bug in LimeSurvey or the surveystructure. You might update to 5.3.12 to check if the bug is still reproduceable. Then you might create a simple survey with just a few questions to reproduce the bug and submit a bugticket in the bugtracker.