Hi
I took the GMAT Online on 11 May 2020 and decided to share a de-brief to help the community. I am doing this because I owe my success to GMAT Club and the community. Thank you

GMAT Online Experience
My overall experience was very smooth. The scheduled time for the exam as 11:00pm. I logged into the system at 10:30pm and managed to upload all necessary documents (Passport/Front Selfie/Room photos) within 10 mins. The exam portal allows you to run a walkthrough of the experience one day before, so that was helpful as I got to know what all photos I will be required to post etc.
I was allocated a Proctor within 5 mins and my exam started at 10:45 pm. Some specific things that stood out from my experience:
The chat window does not always remain open. If you click on 'Chat', it notifies the proctor on the backend. Once the proctor replies to you, the chat widget opens up.
The proctor seemed friendly. Did not interrupt me at all and nor asked me to show my room etc.
Once I was scratching my head and the chat widget popped up. The proctor seemed to assume that I was raising my hand.
I clarified with him and closed the chat
Post Quant+Verbal section, the system showed a break for 5mins (I think the GMAT website mentioned 10min so 5mins was a surprise). Anyway, I did not receive any communication from the proctor about the break pro-actively, so I sent him a message notifying that I will be leaving my desk during the break (for records)
Overall GMAT Prep
I prepared for GMAT starting Jan'20. During my diagnostic attempts, I realized my Verbal (especially Sentence Correction) was quite weak. So I spent 1 week studying the basics of Sentence Correction from the Manhattan book. This was my order of preparation for each section:
Quant: Official Guide Questions -> Mocks
Verbal: Manhattan Theory -> Official Guide Questions -> GMAT Club Practise App
I had also taken the test center GMAT in December'19. I got 710 (Q50 V37) at that time so clearly GMAT Club has been instrumental for me in going from V37 to V44.
Whiteboard Prep
When GMAT Online was announced, I was also a little fazed with the online whiteboard thing. I spent ~14 days practicing Official Guide questions (from the Wiley website) and used the Manhattan whiteboard to practice. I realized within 5-6 days that it will be comfortable and hence registered for the exam.
Closing Notes
I have tried to upload my official score as proof but I guess due to limited points in GMAT Club, I am unable to.
I am eager to help everyone with anything I can. Please ask me any question that comes to your mind and I will be super happy to help.