Registration of only half of property

You may get it (1/2 share of property) transferred and registered in your name.

If the firm is inclined to acced to your request to allot your half share separately with proper demarcation and if there is no objection from your sister in such an allocation, then you can get your share of property registered through the firm itself in your favor. 

To proceed with registration, you are required to obtain a no-objection certificate from your sister. Consequently, you may initiate a suit for partition, followed by registration..

She won't give me any document. She too gets a share in the property but because of issues between her and me, she is refusing to come for the registration. 

Is there any legal way i can make her come for registration so that she gets her half share and I get my half share?

If the firm is ready to deliver share in the property to both of you equally then you can approach the firm to allocate your share in the property separately, if that is not possible then let the firm transfer the share in both the names after which you can file a suit for partition seeking your share with separate possession 

I met my lawyer today. He said I can file a suit with defendants as the firm as well as sister and claim my share through court procedure 

The other partners if not cooperating then you can implead them as defendants along with the company and its partners for this suit for partition or the claim being made.

Well analysed, opined and advised I agree and appreciate the acumen of learned expert

Since the said property was already allocated and physical possession delivered to us several years ago, we have tenants where she is collecting rents from some of them and I am being paid rent by some of them. In this process of partition suit, is it possible to stop the rents since ownership by metres and bounds is not clearly established?

If there was no proper partition done, then you can demand for a proper partition by metes and bounds and if the other party is not inclined to accept this proposal, then you can approach court with a suit for partition for dividing the property by metes and bounds.