South London Gallery is an enjoyable venue to visit with its fantastic bookshop and wonderful cafe. However, one of its primary pitfalls is the separation of the exhibition spaces into two floors. While this may work when several shows are on at once, trying to focus the entire gallery on one exhibition, or artist, is difficult, as one is expected to create conceptual connections despite the imbalance of available space.

The main central gallery is currently taken over by an installation that could double as a relocation of Oscar Murillo's studio space. The floor is covered in stuff – there are discarded gestural paintings; balls of grain which turn out to be corn in its various iterations; the bottle caps of a Poker-labelled beverage; as well as unusual tables strewn with discordant items. At a first look, it appears to be a bit of a crazy craft experiment, with meat grinders and sheets of copper nailed to large tables; however, on closer inspection one discovers that the unifying material is corn. But why on earth is corn of interest in this art context?

It's the installation of various food packaging labels across one wall that indicates Murillo's greater message, and the background to his mystifying exhibition title – the origins of these products are from across the globe, and not just the typically "powerful" continents of Europe and North America. Murillo, who is originally from Colombia, is drawing comparisons between art making and labour with mass production and the now-dominating producing nations of central and south America.

The moulding of corn into unusual shapes that are almost sculptural, with accompanying tools for its preparation, adds another link in the chain of the many guises of corn products and the frequently-unacknowledged effort of the chain's contributors. However, in this instance, the deeper message is lost amongst the debris. The divide between the artistic production – the at-times stunning gestural works and the porcelain sculptures, which channel pre-Colombian storage vessels – does not overlap in any way with these bizarre corn creations. One is left wandering through the space feeling bewildered and out of one's depth, concerned that one's physical interruption is potentially not welcome.

The only particularly recognisable theme is the reference to games, with the chess board patterns on two of the tables and the scattering of 'Poker' chips everywhere adds an undertone of humour, but simultaneously, the reference to gambling gives the sense that your fate is out of your hands. However, this theme is not entirely resolved, and when combined with the intentional detrioration of the space over time, and the mishmash of incongruous materials, the overall mood is bleak and perplexing.

Upstairs, where the exhibition continues, is a film featuring a man trying to sell lottery tickets in La Paila, Colombia, linking to a neighbouring room where Murillo-created lottery tickets are available for the public to purchase. These aren't your typical lottery ticket, and are instead one-of-a-kind entities, thanks to the unique additions of Murillo and/or his family members in the form of paint strokes and the inscription of the purchaser's name by a professional calligrapher. These tickets are not just for show, however, and winners will be drawn on 18 October. How the idea of lottery tickets relates to the first half of the exhibition is obscure and, apart from the similarity in brush strokes on the tickets, one could easily mistake this for a separate exhibition all together. Is Murillo commenting on the corn industry – or others like it – taking a gamble on the lives of its citizens? Or perhaps that developing producing nations, like Colombia, have only that and the lottery as possible revenue options? The references in the press release to ideas of authenticity and value, as well as the public and private sectors of the art world, seems completely left-field and potentially trivialises what is obviously quite a considered concept on Murillo's part.

Too much is trying to be covered here, and the result is dissatisfying. Perhaps the two spaces are meant to be read separately, but their lack of relationship is unnerving. Maybe the accompanying public programmes will shed more light on this exhibition, but one fears that general visitors will feel confused and resentful of this seemingly too abstract offering and leave one mystified as to Murillo's deeper message.

if i was to draw a line, this journey started approximately 400km north of the equator, at South London GallerySophie Keyse reviews Oscar Murillo at the South London Gallery.2