try UNIVERSAL REPEATER here http://www.tp-link.com/en/article/?faqid=250

you posted I have WA 730 RE V 1 = 7 units and it running ok so that means your security is WEP, if that is your case, rule out that one, config.. your TL-WA730RE V2 as you did then connect a Lap via...

read this post specially #12 and #13 http://forum.tp-link.com/showthread.php?3320-W5210G-CPE-cabling-scheme&region=china

you will only find 5Ghz netwroks, TL-WA7510N is a 5Ghz device not like your router at home that is 2.4Ghz

http://www.tp-link.com/en/article/?faqid=173 http://www.tp-link.com/en/article/?faqid=14 http://www.tp-link.com/en/article/?faqid=174 http://www.tp-link.com/en/article/?faqid=437 youn have to change...

http://www.tp-link.com/en/article/?faqid=462 http://www.tp-link.com/en/article/?faqid=463 http://www.tp-link.com/en/article/?faqid=498