Issues after upgrade from v2.9.3 to v2.11.3

Since upgrading a site from v2.9.3 to v2.11.3 I’ve encountered a few issues which leads me to think the update process may have gone wrong.

Issue 1 - Severity: Notice Message: Undefined offset: 97 Filename: libraries/Grid_parser.php Line Number: 157

Issue 2 - Error Number: 1146 Table ‘DBTABLE.exp_low_variables_grid_field_97’ doesn’t exist SELECT * FROM (exp_low_variables_grid_field_97) WHERE entry_id IN (‘162’) ORDER BY row_order asc Filename: models/grid_model.php Line Number: 413

Issue 3 - When trying to use Lasting Impressions Pro add-on I get - Fatal error: Call to undefined method Channel::Channel() in /SITEPATH/system/expressionengine/third_party/lasting_impressions_pro/mod.lasting_impressions_pro.php on line 32

On issue 3 I have communicated with the add-on developer but she cannot replicate the issue her end, so I’m wondering whether it has something to do with the other issues I’m experiencing?

Issue 1 and 2 seems to occur once I have added something to the basket with CartThrob and then I revisit the category pages where I have Low Variables setup to ehlp with category landing page SEO tags.

Does anyone have any ideas where I should start to fix the above please?