"There were two beds standing in the room."
Translation:В комнате стояло две кровати.
No, it mustn't. Tense doesn't make a difference.
When a combination of a number and a noun is the subject of a sentence, we can use both singular and plural forms of the verb. It depends on the meaning.
Singular form is used when
(1) the subject is passive (the two beds were standing = they were just existing there doing nothing);
(2) people/things are not passive, but they are doing the same thing together, and we consider them as a whole. Example: двести человек пришло на концерт (200 people came to the concert). A singular form is used, so we see these people as a mass; we're not interested in what they did individually;
(3) we want to emphasize the number, as slycelote have already said. Двести человек came to the concert. Not 300, not 400.
We use plural form when
(1) the subject is active;
(2) people/things are doing something individually. If 20 students are writing their theses, they can't do it together, right? Each one of them is writing their own thesis by themselves;
(3) emphasis is on the action, not number.
Source: http://new.gramota.ru/spravka/letters/22-spravka/letters/64-bolshinstvo (in Russian)
Oh, now I see that you were talking about the gender of the verb that is ALREADY in the singular form. I'm sorry, my mistake. But it is still not completely correct. If the number ends with "один", the verb needs masculine gender. Also, if the quantity is expressed with a noun (like "пара" = "a couple of"), the verb should take its gender.
Well...depending on what you want to express, I guess... If you're a poet, and you want to express something like an allegory, you want to use the 2 beds as symbols for 2 individuals that feels and thinks, standing there in the room having some sort of relationship...yes, then стояли in pl.
Pls. refer to the explanation by Jukka_S. above!
With regards to the Russian course here on Duo, it's IMHO very good. Far better than many other languages, actually. I don't think we should complain unless we are really certain, and in that case we should use the report function.