[O] problems with beamer under the new exporter: no theme; unable to specify heading level; slides fill from bottom up

[Christopher W. Ryan]

Using org-mode 8.2.4-1 on Linux Mint.

Below is a minimal working example of my problem. The trouble is that
the Berlin theme is not applied--it remains the default theme.

Also, the first slide (after the title slide) seems to "fill from the
bottom up" rather than from the top down. That is, there is a big gap
between the word "Chemistry" and the phrase "Malodorous reduced sulfur
compounds."

Lastly, the H:n option seems to have no effect, regardless of whether
n=1, 2, or 3.

Appreciate any advice.  Thanks.

--Chris Ryan

* Effects of n-butyl mercaptan on human health
  :PROPERTIES:
  :EXPORT_LaTeX_CLASS: beamer
  :EXPORT_LaTeX_CLASS_OPTIONS: [presentation]
  :EXPORT_FILE_NAME: HumanHealthEffectsButylMercaptan.pdf
  :COLUMNS:  %45ITEM %10BEAMER_env(Env) %10BEAMER_act(Act)
%4BEAMER_col(Col) %8BEAMER_opt(Opt)
  :BEAMER_col_ALL: 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0.0 :ETC
  :EXPORT_AUTHOR: Christopher W. Ryan, MD, MS
  :EXPORT_BEAMER_OPTIONS: H:2
  :EXPORT_BEAMER_THEME: Berlin
  :END:

** Chemistry

- Malodorous reduced sulfur compounds

    - Mercaptans

        - methyl mercaptan
        - n-butyl mercaptan
        - ter-butyl mercaptan

    - Hydrogen sulfide