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Your LimeSurvey version: 5.x
Own server or LimeSurvey hosting: Own
Survey theme/template: All default ones
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i'm wondering if anyone else has experience with the default OWASP ModSecurity rules resulting in blocking of access to LS 5.x? If so, I'm looking for guidance on what rules to negate or how to best handle the triggering of the rules for LimeSurvey 5.x

ModSecurity rules (OWASP and others) often breaks parts of LimeSurvey. That is the case since the beginning of LimeSurvey.

Usually you check the audit log file to identify the rules which cause trouble and then exclude these rules via their ID for the URL of LimeSurvey.
Nothing special for LimeSurvey. Just consult the mod security manual or tutorial.