A deadly Ebola outbreak grows. Rebels kill civilians in the streets. And yet the arrival of voting machines in this troubled corner of Democratic Republic of Congo has some especially worried as a long-delayed presidential election promises further upheaval.The machines now arriving by the thousands in this Central African nation are of such concern that the UN Security Council has come calling, the United States has issued warnings and opposition supporters on Friday plan a national protest.As Congo faces what could be its first peaceful, democratic transfer of power, fears are high that the more than 100 000 voting machines will be ripe for manipulation. They also could pose a technical nightmare in a sprawling nation of more than 40 million voters where infrastructure is dodgy — just 9% of DRC has electricity — and dozens of rebel groups are active."We cannot accept people inventing stories that trample our constitution," said Clovis Mutsuva, a Beni resident with the LUCHA activist organisation, which has tweaked the French term "machines a voter" into "machines a voler," or "machines to steal".Obvious challenges While President Joseph Kabila has ended years of speculation by announcing he will respect term limits and step down after the vote, the opposition has loudly protested what it calls Kabila's attempts to ensure that his favored candidate, former interior minister Emmanuel Ramazani Shadary, will win. One opposition leader was blocked from returning from exile. Another, acquitted on war crimes charges at the International Criminal Court, is barred from running.Now attention turns to the voting machines, made by South Korean company Miru Systems, that security researchers say are vulnerable to rigging and print codes that include ballot-specific information that could strip away voters' anonymity. The researchers include experts from Argentina, which rejected the company's machines after learning of the issues.Despite the concerns echoed by diplomats and human rights groups, DRC has plunged into training about 21 000 facilitators on the machines and is introducing the concept in cities, remote towns, Pygmy communities and places like Beni that are essentially war zones. Beni and the surrounding region are in the grip of an Ebola outbreak, which because of the violence could drag on for months before being contained.The government, which has rejected foreign assistance in the election, accuses critics of seeking to further delay a vote that was meant to take place in November 2016. It says the December 23 election will go smoothly despite the obvious challenges. Many disagree.Computer experience "The use of voting machines is a provocation," an opposition politician in Beni, Jose Katsuva Kaneto, told The Associated Press. "A good number of voters have never used computers and they'll be learning on the day of the vote."An electoral commission logistician in Beni to demonstrate the machines dismissed the concerns, comparing voters with no computer experience to the blind and saying they have the right to be assisted by someone of their choice.DRC's elections in 2006 and 2011 had irregularities, Jean Blaise Kamundu told the AP. "With the use of the voting machines, all of the irregularities will disappear. Certain people who exploit them are angry because there won't be any way to do that in this election."DRC has countered concerns by describing the machines as essentially printers, with voters tapping on images of preferred candidates and the choices printed on ballots that are deposited for manual counting.DRC hasn't responded to questions about how results will be transmitted, whether provisions have been made for cybersecurity, how the ballots are stored and whether there will be an independent audit of the results. The electoral commission is considered independent and political parties are often encouraged to witness the voting process.* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and FacebookA UK-backed organisation that tested the machines has warned there is "no buffer for technological malfunction" if Congo wants to complete voting within its 11-hour window, saying people unfamiliar with the touch-screen technology likely will take much longer than expected.The opposition's stance against the voting machines has shown cracks in recent days after top opposition party UDPS behind candidate Felix Tshisekedi announced it would not boycott the election, machines or no. "That doesn't cancel out the criticisms of these machines," said Peter Kazadi, the party's deputy secretary general. "Only election monitoring can save our votes."For some Congolese who watched anxiously as the election was delayed amid sometimes deadly protests over Kabila's extended stay in power, it will be enough to finally stand in line at polling stations and move on."The voting machine is not a big problem," said Salomon Bagheni, a member of Beni's civil society. "Use it or not, the essential thing is holding the elections on December 23 to bring new leadership to this country."