Fix PHP reports script

General information for the website: Details below
Description of requirements/features: We got PHP reports table and chart system from a freelancer and many things do not work - we would like to hire a freelancer who can fix the issues. Everything is in PHP without framework - grid is JSPlatinumGrid and charts are Highcharts.

Issues known so far:

Queries are querying, updating etc on all data but should only work with current user

Emailing is not working - needs to email table as CSV and Highcharts as image (PNG or JPG)

Method of choosing fields is too complex - needs to be simpler. Hard to explain but this doesn't feel like a big piece of work, mainly layout based using JS to display relevant settings

Needs to allow display of sum, avg etc on tables - grid supports this but it doesn't work

Need to allow better filtering on fields - at moment can only filter on included fields on table and cannot filter on chart at all and can only have two filters. Should be more filters , allow to filter on any available field and allow to choose values for filter from database lookup
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