BS901 Balance: Many problems

Hello
After a lot of difficulties to enjoy this balance, I contacted the customer service site Duronic: no response then at dedicated to France: no response and finally to the heading of article submission Amazon on "Contact Seller" and got help in French I needed. The scale itself is no problem but in application it's a catastrophe. There is no application dedicated to the brand you can use both LifeSense or TransHealth that are found on other brands.
I have found that the position on the scale affects the weight display despite being placed on hard ground.
The first: LifeSense wins often enough, I made several installations without convincing results without documentation it was very difficult to make pairing, to understand the operation etc ... There is no documentation available at Duronic.
The 2nd: TransHealth was fairly easy to set up, but I could not get a single profile and can not create another without documentation it is impossible to understand how it works. I had to redo the pairing several times and after a while I gave up.
I sent emails to the parent Transtek in China as well as the person who created the Android version: no response.
Despite the help of Nicolas who made him his job, in the end I requested the return has been accepted.
Note to the balance: 4/5
Note for the SAV (Nicolas): 5/5
Note for applications: 1/5
Manufacturers should think that everyone does not have the innate sense to use an Android application or another and many same pictorial documentation would be welcome (some would do, apparently?)
Charlie