Modify the box Bitrix24

Hello. We need a developer bitrix24, who will finalize in the box bitrix24 cards of transactions, companies, contacts.

In CRM, you need to add 2 fields to the transaction card: company and contacts. Multiple fields (any number) should be (regular functionality does not know how to select a multiple company field).
For companies: companies can have several roles: designer, builder, contractor. Accordingly, this should be indicated in the transaction card. I propose the following option: a person opens a deal card, sees 3 fields with roles, which I wrote about above, adds the necessary companies to these fields.After selecting a company / company, it should be possible to choose one or more contacts from these companies / companies. For contacts: each contact has a field with the designation of the position: secretary, engineer, accountant, etc. The position should be pulled up from contacts (in contacts there is a field indicating the position).The company and contacts should be clickable (clicked on the company - went to the company card, clicked on the contact - switched to the contact card). It should be possible to replace and remove them.

You need to embed a tab in the cards of companies and contacts that will display all active transactions in which these same companies or contacts participate.